互感器二次回路施工验收常见问题分析及防范

Analysis and Prevention of Common Problems in Construction and Acceptance of Secondary Circuit of Mutual Inductor

对某火电厂施工调试期间发生电压互感器一次设备布置差异导致相序相反、一次电压与二次电压相位相反,及电流互感器不同准确级的二次绕组使用错误,不同零序电流互感器对应负荷接线错误等问题,提出了比对设备出厂图纸与设计院图纸差异,规范二次回路接线,设备带电后进行电压与电流暂态、稳态幅值相位检查,对比直流电阻值及伏安特性参数等施工注意事项及验收的方法,有效确保了回路接线的正确性。

This paper is based on the difference in the layout of the primary equipment of the voltage mutual inductor during the construc-tion and commissioning of a thermal power plant,which leads to the opposite phase sequence,the opposite phase of the primary voltage and the secondary voltage,the wrong use of the secondary winding of the current mutual inductor with different accuracy levels,and the wrong wiring of the corresponding load of different zero-sequence current mutual inductors.The method of comparing the difference between the factory drawing and the design institute drawing,standardizating the secondary circuit wiring,checking the voltage and current transient and steady-state amplitude phase after the equipment is charged,comparing the DC resistance value and voltammeter characteristic parameters and other construction considerations and acceptance are put forward,which effectively ensures the correctness of the circuit wiring.